package LeetCode;

public class Code617_mergeTrees {

    public TreeNode mergeTrees(TreeNode t1, TreeNode t2) {
        if (t1 == null || t2 == null){
            return t1 != null ? t1 : t2;
        }
        t1.val += t2.val;
        t1.left = mergeTrees(t1.left, t2.left);
        t1.right = mergeTrees(t1.right, t2.right);
        return t1;
    }
}
